The present invention is concerned with safety features for a microwave oven for the purpose of providing protection to users of such equipment in the event of microwave radiation leakage therefrom.
Microwave ovens are being used more and more extensively for various purposes, particularly for cooking foods in both the home and commercial establishments. The advantage of using these devices in connection with cooking food is the rapidity with which food can be cooked as well as the economical use of power as attends the operation of such devices. At the present time, microwave oven equipment has generally standardized construction particular to the extent that all such ovens operate at 2450 MHz. A problem incident to the use of such devices, is that it is possible for harmful microwave leakage (generally regarded as leakage of more than 10mw/cm.sup.2) to escape thereupon and this can have serious consequences to the user. It is known to provide a microwave oven with an oven door seal to prevent radiation leakage from the oven space. One form of seal involves maintaining a good metal-to-metal contact between the oven frame and the door as by spring-loading the door and/or fixing a metal seal strip at the periphery of the oven opening. Other types of seal commonly used are the so-called "capacitive and choke" type. Notwithstanding the endeavor to provide optimum protection for the oven users, it is possible for radiation leakage to occur, e.g., due to dimished tension in the spring-loaded door device, as well as to the deposit of food or other non-conducting material on the mating metal surfaces of the door and adjacent periphery of the oven opening which prevent achievement of fully sealed closure of the door. Accordingly, it is possible that excessive and dangerous levels of leakage can occur while the oven is in operation. When the oven door is open, a safety switch is employed to cut off power to the unit so that no radiation problems will exist in such condition. But during operation, the user cannot under ordinary circumstances detect the presence of microwave leakage from the oven; it is quite possible for a person to be subjected to possibly harmful dosages of mirowave energy.
It, accordingly, is an object of the present invention to embody in microwave ovens means for deflecting any mirowave radiation leakage away from a user or bystander who is in the vicinity of the oven during operation of the same to thus eliminate such hazard as an incident of the use of the oven, and also for absorbing the deflected microwave radiation leakage and thus converting it to heat.